Notebook[List[Cell[BoxData[List[FormBox[RowBox[List["\[Beta]", "=", FractionBox["k", "z"]]], TraditionalForm], FormBox[RowBox[List["\[Alpha]", "=", FractionBox[RowBox[List["\[Beta]", "+", SubscriptBox["a", "1"]]], "2"]]], TraditionalForm]]], "Input"]]]